Recombinant Anti-pre S2 protein x Anti-S protein Bispecific Antibody (scFv-CH1/CL) is designed to be expressed as two chains. One scFv from an anti-pre S2 protein antibody variable domain is fused to CH1 and the other scFv from an anti-S protein antibody variable domain fused to CL, or vice versa. And the CH1 and CL domains are linked covalently via a natural disulfide bond. This BsAb can bind two antigens simultaneously. It is designed for the research of HBV infection therapy.